Does anyone know if the GI 1qt adapter cap that allows the attachment of a hose to the canteen then your gas mask for drinking will fit the Frontier Pro filter inlet hose? Since that filter will work as a gravity filter, you could maybe use one canteen to gather water, hang it upside down and let the water drain through this "Inline filter" into your container of choice. I USED to have a cap like that and could look at the nipple but I have NO IDEA where it could be.